Hydraulic arrangement

Abstract

A hydraulic arrangement (1) is provided comprising a pressure exchanger (2) having an axis (3) of rotation, and a booster pump (4), said pressure exchanger (2) and said booster pump (4) being connected to each other. Such a hydraulic arrangement should have a good efficiency. To this end a single connection flange (5) is provided between said pressure exchanger (2) and the booster pump (4).

Claims

1. A hydraulic arrangement comprising a pressure exchanger having an axis of rotation, and a booster pump, said pressure exchanger and said booster pump being connected to each other, wherein a single connection flange is provided between said pressure exchanger and said booster pump, wherein said flange comprises a low pressure input of said pressure exchanger and a high pressure channel connecting a high pressure output of said pressure exchanger and a low pressure inlet of said booster pump, wherein said high pressure output of said pressure exchanger and said low pressure inlet of said booster pump are offset relative to each other in a direction of rotation of said pressure exchanger, the direction of rotation being in a circumferential direction of said pressure exchanger, and wherein said booster pump has at its low pressure inlet an inlet area having a width in a radial direction, said width increasing in the direction of rotation.

2. The hydraulic arrangement according to claim 1, wherein said high pressure channel is twisted along an axis of rotation of said pressure exchanger.

3. The hydraulic arrangement according to claim 2, wherein said booster pump has at its low pressure inlet an inlet area having a width in radial direction, said width increasing in the direction of rotation.

4. The hydraulic arrangement according to claim 2, wherein said high pressure channel has a cross section, said cross section increasing in a direction from said pressure exchanger to said booster pump.

5. The hydraulic arrangement according to claim 2, wherein said high pressure channel has a directional component in a radial direction.

6. The hydraulic arrangement according to claim 1, wherein said pressure exchanger has at its high pressure output an outlet area, said inlet area being longer in the direction of rotation than said outlet area.

7. The hydraulic arrangement according to claim 6, wherein said high pressure channel has a cross section, said cross section increasing in a direction from said pressure exchanger to said booster pump.

8. The hydraulic arrangement according to claim 1, wherein said high pressure channel has a cross section, said cross section increasing in a direction from said pressure exchanger to said booster pump.

9. The hydraulic arrangement according to claim 1, wherein said high pressure channel has a directional component in a radial direction.

10. The hydraulic arrangement according to claim 1, wherein said low pressure input of said pressure exchanger has a directional component which is arranged tangentially with respect to a circle line around said axis of rotation.

11. The hydraulic arrangement according to claim 10, wherein said low pressure input has a cross section in a plane perpendicular to said axis of rotation, said cross section increasing in direction of flow.

12. The hydraulic arrangement according to claim 11, wherein said low pressure input has a trailing border in direction of rotation, said trailing border being angled to a radial direction of said pressure exchanger.

13. The hydraulic arrangement according to claim 1, wherein said booster pump, said flange, and said pressure exchanger are arranged in a common casing.

14. The hydraulic arrangement according to claim 13, wherein said common casing is in form of a tube.

15. The hydraulic arrangement according to claim 13, wherein said casing comprises a step in its inner wall and said flange rests against said step.

16. The hydraulic arrangement according to claim 13, wherein said flange is connected to at least one port connection, said port connection running through said casing and fixing said flange in said casing.

17. A hydraulic arrangement comprising a pressure exchanger having an axis of rotation, and a booster pump, said pressure exchanger and said booster pump being connected to each other, wherein a single connection flange is provided between said pressure exchanger and said booster pump, wherein said flange comprises a low pressure input of said pressure exchanger and a high pressure channel connecting a high pressure output of said pressure exchanger and a low pressure inlet of said booster pump, wherein said low pressure input of said pressure exchanger has a directional component which is arranged tangentially with respect to a circle line around said axis of rotation, and wherein said low pressure input has a cross section in a plane perpendicular to said axis of rotation, said cross section increasing in direction of flow.

18. The hydraulic arrangement according to claim 17, wherein said low pressure input has a trailing border in direction of rotation, said trailing border being angled to a radial direction of said pressure exchanger.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 shows a schematic longitudinal section of a hydraulic arrangement having a pressure exchanger and a booster pump,

(2) FIG. 2 shows a schematic sectional view of a flange at a high pressure side of the pressure exchanger according to a section II-II of FIG. 1, and

(3) FIG. 3 shows a schematic section III-III of FIG. 1 at a low pressure side of the pressure exchanger, and

(4) FIG. 4 shows a casing for the hydraulic arrangement.

DETAILED DESCRIPTION

(5) All FIG. show the same elements with the same reference numerals.

(6) A hydraulic arrangement 1 comprises a pressure exchanger 2 having an axis 3 of rotation. Furthermore, the hydraulic arrangement 1 comprises a booster pump 4 in form of a vane cell pump. However, other types of pump are basically possible.

(7) The pressure exchanger 2 and the booster pump 4 are connected to each other by means of a single flange 5.

(8) The pressure exchanger 2 comprises a number of cylinders 6 which are arranged in a cylinder drum 7. The cylinder drum 7 is rotatable about the above mentioned axis 3.

(9) The pressure exchanger 2 comprises a low pressure input 8, a low pressure output 9, a high pressure input 10 and a high pressure output 11.

(10) Such a hydraulic arrangement 1 can be used in a reverse osmosis system, for example, to desalt sea water. In the operation of such a reverse osmosis system seawater, i.e. salted water, is pressed with a rather high pressure level through a membrane to gain purified water. The rest of the water, so called concentrate has still a relatively high pressure, but has to be wasted. In order to recover the pressure energy, the concentrate is supplied to the high pressure input 10 of the pressure exchanger 2. The low pressure input 8 is supplied with seawater which pushes out the remaining concentrate through the low pressure output 9. When the cylinder drum 7 rotates, the fresh sea water is pressurized by the pressure of the concentrate at the high pressure input 10 and pushed out with elevated pressure through the high pressure output 11, as it is known.

(11) In most cases it is necessary to increase the pressure level of the fresh sea water further to pump it through the membrane. To this end the booster pump 4 is used.

(12) The single flange 5 between the pressure exchanger 2 and the booster pump 4 has a number of advantages. In contrast to a flange formed by a stack of plates there is less flow resistance because there are no transitions between neighboring plates of the stack. Furthermore, the single flange 5 can be made relatively stable so that it can withstand higher pressures without being deformed.

(13) The pressure exchanger 2 has a first valve plate 12 at one axial end and a second valve plate 13 at the second axial end. The first valve plate 12 rests against a first port plate 14. The second valve plate 13 rests against a second port plate 15. The first port plate 14 is supported by the mechanically stable flange 5.

(14) The low pressure input 8 of the pressure exchanger 2 is provided within the flange 5. The flange 5 furthermore comprises a high pressure channel 16 connecting the high pressure output 11 of the pressure exchanger to a low pressure inlet 17 of the booster pump 4. This low pressure inlet 17 is formed in an inlet area 18 (FIG. 2) which is offset relative to the high pressure output 11 of the pressure exchanger 2. This offset is symbolized in FIG. 2 by an angle .

(15) The high pressure output 11 of the pressure exchanger 2 is formed in an outlet area 19, for example, a kidney-opening in the first port plate 14. The inlet area 18, which basically is a kidney-shaped recess as well, and the outlet area 19 overlap each other. However, the inlet area 18 is longer in direction of rotation than the outlet area 19. The offset is defined between the centers of the inlet area 18 and the outlet area 19 in circumferential direction.

(16) To achieve a connection between the outlet area 19 and the inlet area 18, the high pressure channel 16 is twisted along the axis 3 of rotation of the pressure exchanger 2. Furthermore, as can be seen in FIG. 1, the high pressure channel 16 has a directional component in radial direction, i.e. it runs at least partially with an angle relative to the axis 3 of rotation.

(17) As can be seen in FIG. 2, the outlet area 19 has a smaller size than the inlet area 18. To achieve a smooth transition, the high pressure channel 16 has a cross section increasing in a direction from said pressure exchanger 2 to said booster pump 4 thereby decreasing the differential throttling resistance over the length.

(18) FIG. 3 shows schematically the situation in the region of the low pressure input 8 of the pressure exchanger 2. Incoming fluid symbolized by arrows 20 passes through the low pressure input 8. In the plane shown in FIG. 3, the low pressure input 8 has a section increasing in flow direction. The low pressure input 8 has a trailing border 21 which is angled to a radial direction of the pressure exchanger. Therefore, as can be seen in FIG. 3, the incoming fluid is directed in direction 22 of rotation of the cylinder drum 7. Therefore, less energy is necessary to accelerate this incoming liquid when this liquid enters the cylinders 6 of the pressure exchanger 2.

(19) Although the embodiment describes is preferred, it is also possible to use the construction of the low pressure input as shown in FIG. 3 done, i.e. without the optimized high pressure channel 17. It is furthermore possible to use the optimized high pressure channel 17 alone without the construction of the low pressure input 8 shown in FIG. 3.

(20) FIG. 4 shows schematically a casing 23 adapted for receiving the pressure exchanger 2 in a section 24 of the casing and of the booster pump 4 in a section 25 of the casing. Pressure exchanger 2 and booster pump 4 are not shown for the sake of clarity.

(21) Casing 23 is of tubular form, i.e. casing 23 forms a hollow cylinder. Casing 23 comprises an inner wall 26 running in circumferential direction. Said inner wall 26 comprises a step 27 against which flange 5 rests. Step 27 defines the axial position of flange 5 within casing 23.

(22) Low pressure input 8 is connected to a port connection 28. Port connection 28 is guided through casing 23 and fixes flange 5 relative to casing 23. Furthermore, an outlet 29 is shown connected to a further port connection 30, said port connection 30 serving as fixation of the flange 5 as well.

(23) When the hydraulic arrangement with pressure exchanger 2, booster pump 4 and flange 5 is assembled, casing 23 surrounds these three elements in circumferential direction so that only very few additional connecting elements are necessary to hold together these three elements.

(24) While the present disclosure has been illustrated and described with respect to a particular embodiment thereof, it should be appreciated by those of ordinary skill in the art that various modifications to this disclosure may be made without departing from the spirit and scope of the present disclosure.